Chlamydia/Gonococcus − Client-provided Aliquot

Test Details

Use

Detect Chlamydia trachomatis and/or Neisseria gonorrhoeae

Limitations

“Because cytology/HPV testing and STD testing address different clinical questions, aliquot removal may not be suitable for all clinical situations. Physicians and other persons responsible for ordering clinical tests should be familiar with the following.

• There is no evidence of degradation of cytology results by aliquot removal, however, this cannot be ruled out for all specimens. As with any subsampling step in anatomic pathology, chance misallocation of diagnostic cells may occur if they are very rare. If negative results from the specimen do not fit with the clinical impression, a new specimen may be necessary.

• Aliquot removal from low-cellularity may leave insufficient material in the PreservCyt® sample vial for preparation of a satisfactory ThinPrep® Pap Test™ slide.

• Aliquot removal may leave insufficient material in the PreservCyt® sample vial for performance of ancillary testing (ie, reflexive HPV testing) using the residual specimen following preparation of a ThinPrep® Pap Test™.

• Cocollection of separate samples for the ThinPrep® Pap Test™ and STD testing may be considered in lieu of aliquot removal.

• When opting for concurrent cytologic and STD testing, providers should consider risk and clinical history (eg, disease prevalence, patient age, sexual history, or pregnancy) as well as specimen suitability (ie, exudates of bleeding) that can impact diagnostic reliability.1,2

Minimum Volume

Container

Collection

ThinPrep® preservative vial processing: ThinPrep® instructions for removal of material are specifically listed in the ThinPrep® 2000 and ThinPrep® 3000 System Operator's manual Addenda. These instructions include the following statement. “Good laboratory practices should be followed to avoid introducing contaminants into either the PreservCyt® sample vial (ThinPrep® vial) or the aliquot. It is recommended to use powder-free gloves and an individually wrapped, disposable pipetting device with an aerosol barrier tip that is sized appropriately for the volume being withdrawn and dispensed. You should not use serological pipettes. In order to minimize the potential for cross contamination, aliquot removal should be performed in an appropriate location outside an area where amplification is performed.”

LabCorp uses the following procedure and believes it is consistent with the previous instructions as well as with the amplified assay that will be performed on the specimen to be sent. Note: For testing, aliquots must be transferred to Aptima® specimen transport tubes or Aptima® Unisex specimen transport tubes (both referred to as “Aptima® tube” in the following procedure) from ThinPrep® vials within seven days of specimen collection when ThinPrep® vials are stored at 15°C to 30°C.

Aliquot Removal Procedure

1. Put on clean gloves.

2. Wipe down work surfaces and pipettors with 1:1 bleach:water solution.

3. Allow bleach to contact work surfaces and pipettors for at least one minute and then follow with a water rinse.